comparing Mysterio to Bleu Demon, is like saying Big Show is a clone of Andre the Giant....

Lucha Libre during Blue Demons era has nothing to do with what current Luchadores can do. (hell even his dad the orginal Rey Mysterio has nothing on his son, i dare to say.)
Same with the Guerreros or people you may be familiar with.

Show was a clone of Andre when he started and was a carbon copy of the guy for years. Dont know how his name is brought up....

BD was doing the extreme lucha style, along with El Santo decades ago and sure enough, Mysterio was obviously a student. Not to mention the 619, a move that Mysterio gets credit for creating, was done again, decades ago by Sayama.